This article is from the Amiga FAQ, by Ignaz Kellerer with numerous contributions by others.
Fred Fish has started in the middle eighties to collect freely distributable software on floppy disks. There are 1000 disks and very much good stuff on it. Most Amiga dealers sell them and most magazines contain addresses of people mailing them to you for about 3$ per disk or less. Fred Fish has terminated offering software on floppy disks. Instead, there is a dealer who offers the new software from the CD-Roms on floppy disks.
There are some things which can be found on the Fish disks, but not on Aminet. However, you can get them with FTP. See Fish disk xxx.